But I had to set this under Virtualmin, Addresses and Networking, Change IP address.

When I tried doing this under Virtualmin, Server Configuration, Change IP Address, it failed for 2nd and further domains as I got an error that the 192.168.1.77 IP is already in use.

Now all I got to figure out is how to get Webmin working with a self signed or LetsEncrypt SLL and it's a win :-)
The SSL part of Webmin (not Virtualmin, SSLs work for each domain) is not working and can't get it to work, with the self signed certificate I get NET::ERR_CERT_COMMON_NAME_INVALID with the browsers, LetsEncrypt returns me an error: